MS-20 filter clone (rene schmitz) producing only noise

[habibelhabab]

Hello DIYers,

I recently dug into DIYing because I wanted an analog filter.
I'm now trying to make rené schmitz MS-20 filter clone to work,
which I've soldered to a piece of print using this PCB as a guide:
http://www.analog-synth.de/synths/mod2/ms20filter/rene_ms20_filter_clone rev 4.pdf

Now when I test it, it makes only a very loud noise with lots of cracking sounds. Sometimes the input can be heard through the noise but mostly it's just nothing. The clipping leds keep blinking randomly as well.
It's frustrating because I already built this
http://electro-music.com/forum/viewtopic.php?highlight=ms20+filter&t=20668
and though it had a similar problem at first, i got it working in the end (but don't know why)

I'm kind of desperate for some tips, because I double-checked it several times and I'm 99% positive that the wiring is correct...
I also had a spare for each of the IC's so I replaced them all, but the problem remains...

EDIT: solved, after completely disassembling the board, I discovered solder that crept up the legs of a IC socket, kind of connecting them on the topside of the board. Lesson: Watch out for using too much flux!!
Rebuilding now...

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[eXisteNz]

Hi i'm nico, from italy, i cant find a clear project for the ms-20 filter...could you send me something about this project? The link doesn't work anymore, i really appreciate if you could send me the project files (schematics, pcb, part list and layouts) my mail is : ufo@hotmail.it

thank you so much, and congratulations for your filter!
have fun
n